Year: 2016
Type: article
Abstract: . We propose to use the ensemble Kalman smoother (EnKS) as the linear least squares solver in the Gauss–Newton method for the large nonlinear least squares in incremental 4DVAR. The ensemble approach is naturally parallel over the ensemble members and no tangent or adjoint operators are needed. Further, adding a regularization term results in replacing the Gauss–Newton method, which may diverge, by the Levenberg–Marquardt method, which is known to be convergent. The regularization is implemented efficiently as an additional observation in the EnKS. The method is illustrated on the Lorenz 63 and the two-level quasi-geostrophic model problems.
Authors: J. Mandel, E. Bergou, S. Gürol, S. Gratton, I. Kasanický
Institutions: Czech Academy of Sciences, Czech Academy of Sciences, Institute of Computer Science, University of Colorado Denver, Université Paris-Saclay, Mathématiques et Informatique Appliquées du Génome à l'Environnement, Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique, École Nationale Supérieure d'Électrotechnique, d'Électronique, d'Informatique, d'Hydraulique et des Télécommunications
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,412
OpenAlex ID: W3099813880